Velbon SPT-1 Lens Supporter
The SPT-1 Lens Support Tripod Mount adds stability when shooting with a heavy telephoto lens. It fits between the foot on the lens's tripod collar and a tripod. The SPT-1 can attach to a quick-release plate, Arca-type compatible clamp, or directly to any 1/4"-20 threaded screw on a tripod or head.
The attachment point can move forward or backward so that the height-adjustable mounting column can be located in the correct position to screw into your camera's tripod mount.